Conventionally, parts have been attached to a product with bolts by a robot in the manufacturing line of automobiles. Such bolts are supplied to the robot by way of a parts feeder.
The parts feeder includes a hopper, and when an operator places the bolts into this hopper, the bolts thus placed are aligned and discharged (refer to Patent Document 1).
However, since the bolts that can be aligned by one parts feeder are of one type, a plurality of parts feeders become necessary if several types of bolts are used in a manufacturing line. Accordingly, a problem has been posed that an increase in cost is inevitable since parts feeders are expensive.
Therefore, an extraction rack to which the bolts are supplied and a robot that grips and aligns the bolts supplied to the extraction rack have been proposed. According to this robot, it is possible to decrease the cost even if any type of bolt is supplied, since this robot can grip and align any type of bolt. Patent Document 1: Japanese Unexamined Patent Application Publication No. H6-126555